A France-based rights activist who was at the heart of the 1989 student-led democracy protests in Beijing's Tiananmen Square has died suddenly at the age of 48.

Zhang Jian, who was injured during the People's Liberation Army (PLA) crackdown on unarmed civilians in 1989, lost consciousness en route between Thailand and Paris after going incommunicado on April 15, his friends and fellow activists said.

He was sent to hospital in Munich, Germany, for emergency treatment, but later died.

Zhang's friend Han Rongli said via Twitter that the French embassy in Germany was only then notified of his death.

His death, coming as it does ahead of the 30th anniversary of the Tiananmen massacre, has sent shock waves through the overseas Chinese democracy movement.

Qin Jin, deputy chairman of the Federation for a Democratic China, said Zhang's body has yet to be repatriated to France, where he had obtained citizenship.

"We have only received verbal notification of Zhang's death so far ... and we don't have a death certificate yet," Qin told RFA.

"We are arranging for people to see to the death certificate and the [repatriation of] remains," he said. "We can't set the time of the memorial service until those two things have happened."

"I dont know if his family can leave China," Qin said.

Liao Yiwu, a Chinese dissident writer living in Germany, tweeted that the cause of the coma was "ascites of the liver," referring to the abnormal accumulation of fluid in the spaces between tissues and organs in the abdominal cavity.

Former 1989 student leader Wang Dan said via his Facebook page that those who were left behind would have to carry on working for democracy in China.

"Over the years, we have sometimes agreed and sometimes disagreed, but I have always seen him as my comrade-in-arms with a shared history and shared hopes," Wang said. "Now he is at rest, and we who are left behind will have to dry our tears and keep going."

"A strong sense of justice"

Chinese political scholar and exile dissident Wang Juntao said he was greatly saddened by Zhang's loss.

"Zhang Jian may have had conflicts with some people because of his personality, but he had a strong sense of justice," Wang said.

"At the same time, because he was a Christian, he had a very strong sense of right and wrong, and tried to do a good job in the democratic movement and of his faith," he said.

Magazine editor and political commentator Hu Ping painted a picture of a lively and self-educated man who brought plenty of enthusiasm to the overseas democracy movement.

"I met Zhang Jian several times, and had the impression that he was very enthusiastic," Hu said. "Zhang didn't have much formal education, but was very talented, writing essays, poems and ballads that really caught on."

"I am very saddened by his death," he added.

Zhang had visited Thailand several times before his death to better understand the situation of Chinese refugees there.

Thailand-based refugee Ai Ming said she had received phone calls from Zhang offering help and advice with her asylum application, and he had also met with her husband, Yang Chong, to find out more about the plight of Chinese refugees in Thailand.

"He did a lot for refugees in Thailand last year, including visiting them in immigration detention centers, and helping sort out various things, then fighting for their rights as refugees in Geneva," Ai said.

"I was shocked at his death," she said. "I knew he was sick, but this was so sudden."

Born in 1970 in the Tongzhou district of Beijing, Zhang was a student at the Beijing Institute of Physical Education at the time of the weeks-long student-led mass protests in Tiananmen Square.

When the PLA moved in to clear the city with machine guns and tanks, Zhang took three bullets to the leg. These were only removed by doctors in Paris in 2008.

He succeeded in fleeing China to evade the crackdown that followed the end of the democracy movement, and was eventually offered political asylum and French citizenship.

He had previous served as vice chairman of the Federation for a Democratic China.

Reported by Han Jie for RFA's Mandarin Service, and by Wen Yuqing for the Cantonese Service. Translated and edited by Luisetta Mudie.

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